Patent GB-262725-A (GB)
Title: Improvements in or relating to speed indicating apparatus
IPC: G01P1/10
Filed: 1926-08-13
Abstract: 262,725. Gambarotta, P. Dec. 12, 1925, [Convention date]. Centrifugal speed indicators with signalling apparatus.-In a group or particular speed signalling device such as that described in Specification 207,650, (1) the ball or like device after it has given its signal cannot be restored to normal until the vehicle has stopped and a suitable manipulation by the driver has been performed, (2) the distance run at the excess speed is registered on a counter, (3) luminous signals are provided to correspond with the various balls, (4) a single ball only may be used and its drive transmission ratio be varied to give a signal when a selected one of several speed groups is exceeded; (5) other methods of driving the ball by means of the centrifugal masses are suggested; (6)a forewarning signal to intimate the approach to the critical speed is provided. (1) The governor socket 5 supports pivoted catches 3 pressed towards the hollow driving shaft 1 by an elastic band 6. When the speed is excessive the descent of the socket permits the tips of the catches to enter slots 2 in the shaft and so maintain the masses 9 extended and the signal in " excess speed " condition. In this form the casing n is thus rendered stationary, being no longer driven by engagement of the masses. In order to restore the apparatus to normal condition a seal H has to be broken to release a knob 12 which may then be raised, carrying with it a spindle 11 terminating in a cone 10 adapted to displace the catches outwards and allow the spring 13 to raise the socket. (2) The driving shaft 1 contains another spindle 20 secured at its upper end to the governor socket and at its lower end co-operating with a pivoted arm 25. When the group speed is exceeded the spindle has descended sufficiently to engage and rotate the arm so that a lug 26 may advance a counter 28. Where a number of signal balls operative at different speeds are employed, a clutch for each may be interposed in order to select which counter shall receive the registrations. (3) This same spindle 20 carries a disc 29 to engage a contact 31 and thus break the circuit of a lamp 32 coloured to correspond with the casing n. The lamp might however be switched in and out by contact of the weights with the ball n and it might be arranged inside the ball if this is transparent. (4) To vary the transmission ratio and therefore the point at which the signal functions, a pair of differently-sized pulleys 46 driven by a single belt 36 can be displaced axially on the drive shaft 34. To signal which ratio is in action, the pulleys are connected by a rod 35 with a cylindrical rack 40 engaging a pinion 41 on a coloured disc 43 the coloured areas of which have an aperture closed by coloured transparent material to vary the light from lamp 32 accordingly. (5) The driving connection between the governor masses 9 and the casing n may comprise a toothed wheel 48 normally engaged by toothed rollers 50 mounted on the masses and friction-held by spring blades 51. Alternately the masses may drive the casing by bearing directly against a rubber ring thereon. (6) A ball n' is driven at excess speeds by masses on a shaft rotated through variable gear comprising roller 55 and disc 54. In place of this warning ball, the cap 14 may be painted with a conspicuous spot or segment.